There are several types of masonry blocks including large hollow precast concrete blocks used in construction. The hollow blocks can be used for load-bearing walls of buildings and for the constructing of retaining walls. The hollow blocks are reinforced with core filled concrete columns and steel reinforcement bars. The blocks have one or more vertical apertures extending therethrough, and have either cast smooth sides or they may be split-faced blocks that include a rough, stone-like texture on at least one face of the block.
If the blocks are to be made into split-face blocks, they are first moulded as two blocks joined together and once cured are passed through a splitter. This causes the double block to fracture and form a rough, stone-like texture on one face of each block. Corner blocks are moulded as double blocks with end portioned that are also slit off to reveal two perpendicular sides with rough, stone-like texture.
The vertical apertures extending through the masonry blocks permit the positioning of the steel reinforcement bars and allow core fill concrete to run vertically and horizontally through the block to compensate for the lack of tensile strength of the wall.
Conventionally the masonry blocks are stacked and held together with concrete mortar to form the desired length and height of the wall. This however required the cores to be cleaned of excess mortar prior to filling with the core fill concrete. More recently interlocking concrete block systems have also been developed. These systems may include plastic locating bridges and the blocks may include moulded lugs that engage with the underside of an overlying block or blocks to thereby locate the overlying courses of blocks. The ends of the blocks are typically fixed to abutting blocks using a concrete mortar or other adhesive.
There are also various mortarless interlocking concrete block systems currently available. However the core fill concrete has a tendency to bleed out between the vertical interfaces between adjacent blocks during construction of the wall, which necessitates cleaning or rendering of the wall surface.
Furthermore, a user must still construct wooden formwork at the corners of the walls or use an adhesive such as mortar on the vertical sides of the blocks to prevent blowout that results in a block becoming dislodged from the wall. Blowout of a wall can be a costly and time-consuming problem to rectify. This increases the time required to construct the wall and means that under certain weather conditions the wall cannot be constructed.
It should be appreciated that any discussion of the prior art throughout the specification is included solely for the purpose of providing a context for the present invention and should in no way be considered as an admission that such prior art was widely known or formed part of the common general knowledge in the field as it existed before the priority date of the application.